| annular staphyloma | A staphyloma extending around the periphery of the cornea. (05 Mar 2000) |
|---|---|
| annular stop | <microscopy> The opaque ring-shaped stop with a small central opening usually placed in the objective back focal plane to provide dispersion staining. (05 Aug 1998) |
| annular stricture | A ringlike constriction encircling the wall of a canal. (05 Mar 2000) |
| annular synechia | Adhesion of the entire pupillary margin of the iris to the capsule of the lens. (05 Mar 2000) |
| annular syphilid | Cutaneous lesions of secondary syphilis in which the papules form annular lesions with raised papular borders and clear central portions. (05 Mar 2000) |
| Gerlach's annular tendon | fibrocartilaginous ring of tympanic membrane |
| moss-lichen wetland | <ecology> A wetland dominated by mosses (mainly peat mosses) and lichens with little taller vegetation. (09 Oct 1997) |
| Wilson's lichen | A primary disorder of the skin resulting in violaceous, polygonal, flat skin lesions that often pruritic (itchy). Seen commonly on the wrists, shins, lower back and genitalia. Involvement of the scalp may lead to hair loss. The cause of lichen planus is unknown, but may occur after the use of a drug (thiazide diuretics, phenothiazines, antimalarials). Treatment with topical corticosteroids is common. In most patients, spontaneous regression of the disease will be seen 6 months to 2 years after onset. (27 Sep 1997) |
| lichen | A large group of symbiotic associations between fungi and green and occasionally blue green algae. Several genera of algae and of fungi are involved and the associations are so stable and of such varied but distinct types that the lichens have been classified into genera and species. A variety of incompatibility phenomena are often manifest between individual lichens. Confined to terrestrial habitats and often used as indicators of pollution status of the environment. (18 Nov 1997) |
| lichen acuminatus | A primary disorder of the skin resulting in violaceous, polygonal, flat skin lesions that often pruritic (itchy). Seen commonly on the wrists, shins, lower back and genitalia. Involvement of the scalp may lead to hair loss. The cause of lichen planus is unknown, but may occur after the use of a drug (thiazide diuretics, phenothiazines, antimalarials). Treatment with topical corticosteroids is common. In most patients, spontaneous regression of the disease will be seen 6 months to 2 years after onset. (27 Sep 1997) |
| lichen agrius | Acute papular eczema of severe type. Synonym: Celsus' papules. (05 Mar 2000) |
| lichen albus | Chronic lichenoid dermatitis with depigmentation. (05 Mar 2000) |
| lichen amyloidosis | Localised cutaneous amyloidosis with pruritic brownish-red papules, most commonly on the lower legs, due to amyloid infiltration of the papillary dermis. Synonym: amyloidosis cutis, lichen amyloidosis. Origin: G. Leichen, lichen, a lichen-like eruption + eidos, resemblance (05 Mar 2000) |
| lichen annularis | <dermatology> Benign granulomatous disease of unknown aetiology characterised by a ring of localised or disseminated papules or nodules on the skin and palisading histiocytes surrounding necrobiotic tissue resulting from altered collagen structures. (12 Dec 1998) |
| lichen haemorrhagicus | A papular eruption due to haemorrhage into the hair follicles. (05 Mar 2000) |